During the initial start-up and operation of a work vehicle, hydraulic fluid in the work vehicle may be relatively cold, especially when the work vehicle is operating in a cold climate. The cold hydraulic fluid may be viscous, which may reduce the response of hydraulic functions of the work vehicle, reduce hydraulic efficiency due to higher pressure drops in the work vehicle, and cause problems with power control of the work vehicle, for example.
When the cold hydraulic fluid eventually warms up to a normal operating temperature and becomes less viscous, the work vehicle may function and react properly. The work vehicle may include one or more coolers to maintain the hydraulic fluid at its normal operating temperature. However, during the initial start-up and operation of the work vehicle, such coolers may increase the time required for the cold hydraulic fluid to warm up to its normal operating temperature. The time required for the cold hydraulic fluid to warm up may be especially long when the work vehicle uses a fixed fan drive system that lacks the ability to reduce the cooling effect of the cooler, for example.
Prior attempts to improve the warm-up of hydraulic fluid in a work vehicle require additional equipment, such as thermostat-based flow control valves, which may be expensive and time-consuming to install.